<div id="app">
  <add btn="h"></add>
</div>

<script>
  var vm = new Vue({
    el: '#app',
    data: {
      h: "hello"
    },
    components: {
      "add": {
        props: ['btn'],
        template: "<button>btn：{{btn}}</button>",
        data: function () {
          return {btn: "123"};
        }
      }
    }
  });
</script>
